Injured intervertebral discs are generally treated with bed rest, physical therapy, modified activities, and pain medications for substantial treatment durations. There are also a number of treatments that attempt to repair injured intervertebral discs and to avoid surgical removal of injured discs. For example, disc decompression is a procedure used to remove or shrink the nucleus, thereby decompressing and decreasing the pressure on the annulus and nerves. Less invasive procedures, such as microlumbar discectomy and automated percutaneous lumbar discectomy, remove the nucleus pulposus of a vertebral disc by aspiration through a needle laterally inserted into the annulus.
Another procedure involves implanting a disc augmentation device in order to treat, delay, or prevent disc degeneration or other disc defects. Augmentation refers to both (1) annulus augmentation, which includes repair of a herniated disc, support of a damaged annulus, and closure of an annular tear, and (2) nucleus augmentation, which includes adding or removing material to the nucleus. Many conventional treatment devices and techniques, including open surgical approaches, involve muscle dissection or percutaneous procedures to pierce a portion of the disc under fluoroscopic guidance, but without direct visualization.
Several treatments also attempt to reduce discogenic pain by injecting medicaments or by lysing adhesions in the suspected injury area. However, these devices also provide little in the form of tactile sensation for the surgeon or allow the surgeon to atraumatically manipulate surrounding tissue. In general, these conventional systems rely on external visualization for the approach to the disc and thus lack any sort of real time, on-board visualization capabilities.
Accurately diagnosing back pain is often more challenging than expected and often involves a combination of a thorough patient history and physical examination, as well as a number of diagnostic tests. A major problem is the complexity of the various components of the spine, as well as the broad range of physical symptoms experienced by individual patients. In addition, the epidural space contains various elements such as fat, connective tissue, lymphatics, arteries, veins, blood, and spinal nerve roots. These anatomical elements make it difficult to treat or diagnose conditions within the epidural area because they tend to collapse around any instrument or device inserted therein. This may reduce visibility in the epidural space, and may cause inadvertent damage to nerve roots during device insertion. Also, the insertion of a visualization device may result in blocked or reduced viewing capabilities. As such, many anatomical elements within the epidural space may limit the insertion, movement, and viewing capabilities of any access, visualization, diagnostic, or therapeutic device inserted into the epidural space.
Dilators are often used to give access to the disc space while keeping the nerve root out of the surgical area. However, the surgeon is, then, limited in operating space by the space of the interior cavity of the dilator.